Risky sexual activity and substance use are widespread among adolescents in both the United States and South Africa and are associated with detrimental long-term outcomes such as addiction and sexually transmitted infections (STIs) such as HIV. Research aimed at further understanding the etiology and prevention of these behaviors is needed. Extant research suggests that adolescents' leisure experiences play an important role in development of risky behaviors, and that leisure may be an important context for the prevention of risky behaviors. However, few studies have examined concurrent changes in leisure activity participation and risky behaviors, thus limiting the development of leisure-oriented preventive interventions. [unreadable] [unreadable] The overarching aim of the current project is to elucidate the relationship between leisure activity [unreadable] participation and the outcomes of substance use and sexual activity by utilizing innovative methods (Latent Class and Latent Transition Analysis) and a longitudinal dataset rich with information pertaining to the variables of interest. Latent classes of activity participation and sexual and susbtance use related risk behaviors wi|l be created and linked longitudinally. Data for the proposed study comes from the ongoing HealthWise South Africa project. HealthWise aims to prevent HIV and substance use by encouraging safer sexual practices, substance use resistance, and prosocial, personally meaningful leisure time use among adolescents. The program is currently being implemented with adolescents in Mitchell's Plain, South Africa. Thus far, approximately 6400 students have been enrolled in this study and provide data approximately every six months over a period of three years. Results of this study will inform future adaptations of HealthWise as well as the development of other HIV and substance use prevention programs. [unreadable] [unreadable] [unreadable]